Bacteriocin Production in Bacillus cereus Food Isolates with Molecular Detection of cerA gene

Abstract

Sixty-three Bacillus cereus strains isolated from food samples. All strains were subjected to DNA sequencing for 16S rRNA for identification. 15 strains were registered at GenBank of NCBI and given new accession numbers. 41.26% of the isolates showed bacteriocinogenicproduction activity against four bacterial speciesviz,Bacillus cereus, Staphylococcus aureus, Escherichia coli and Salmonella sp. Presence of cerA gene coding for cericidine(a type of bacteriocin) was detected in 7.69% of the isolates that produced bacteriocin. Bacterionwas precipitated by ammonium sulphate and purified by dialysis. Antimicrobial activity of precipitated bacteriocin against the four types of bacteria showed the effect on Bacillus cereus and Staphylococcus aureus growth but not on Escherichia coli and Salmonella spp.The produced bacteriocin has a molecular weight ranging from 47-54 KDa.Estimation of the concentration and physical and chemical properties of bacteriocin were also investigated.